1. Field of the Invention
The invention relates to an electric plug and socket connection.
2. Description of the Prior Art
Electric plug and socket connections are known. During the production of the electrically conducting connection or, respectively, during disengagement or releasing of same, the current-carrying contact faces between two contacts to be paired become gradually larger or, respectively, gradually smaller whereby, in case of current-carrying connections, the specific face load decreases or, respectively, increases. In case of high-loaded contact-providing pairs, contact face parts and zones of contacts can be overloaded, even if perhaps only for a short time, which overloading interferes with the functioning (zone-incremental increase of the transfer resistance) and life-time of the contacts. This danger exists in particular in case of plug and socket connections for loud-speaker systems with high power, as they are employed for example in case of professional music presentations, even though this danger is not limited to systems and plug and socket connections of this kind. In case of an electric plug and socket connection, to which the present invention relates, this refers to such plug and socket connections for energy and information transfer.
A plug is known from the U.S. Pat. No. 4,464,001, where the two casing parts are connected to each other with a so-called bayonet-type coupling. In order to achieve this connection, the two casing parts are initially moved towards each other, in a coaxial position relative to each other, and then they are rotated towards each other. Imaginary parts of front face sections, disposed opposite to each other, consequently experience a relative motion with respect to each other which is initially disposed parallel to the axis of the plug and, subsequently thereto, a relative cross motion on a circular arc line. For this purpose, this plug is also provided as a single-pole plug. The plug includes a central contact pin, as well as a contact bush which receives this contact pin. A plug with such a locking can therefore not be formed as a multiple plug without difficulties.
A plug connection is illustrated and described in the U.S. Pat. No. 4,550,967, where the two plug parts are coupled to each other by an axial linear motion. A cylindrical insulator is embedded in one plug part, where contact bushes are resting in the cylindrical insulator. These contact bushes receive contact pins, which are supported in the counterpart. This plug connection includes a snap lock coupling, which serves to secure the coupled plug parts in their position. On the outside at the cylindrical casing of the plug part, there are disposed cylindrical bolts at a uniform distance from each other, which cylindrical bolts are received by grooves in the counterpart. On the side of such a groove, there are disposed annular springs, which protrude with one part of their circumferential section into the groove. If the two plug parts are joined, then the bolt slides along the groove, reaches the narrow sections, and presses the springs toward the outside and thus passes into the rear-side or end-side part of the groove. In this position, the bolts release the springs again, which springs then spring into the groove cross-section and thus form a narrowed locking location for this bolt. This snap lock coupling is constructed in a very expensive manner.